Apparatus for feeding water to steam boilers



p I T. J. SULL|VAN 2,131,335

APPARATUS FOR FEEDING WATER T0 STEAM BOILERS Filed June 5, 1936 2Sheets-Sheet 1 Jnnentor:

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P 1938. T. SULLIVAN Q 2,131,335

I APPARATUS FOR FEEDING WATER TO STEAM BOILERS Filed June 5, 1936 2Sheets-Sheet 2 3nventor:

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Patented Sept. 27, 1938 UNITED STATES APPARATUS FOR FEEDING WATER TOSTEAM BOILERS Timothy J. Sullivan, Butte, Mont., assignor to SullivanValve and Engineering Company, Butte, Mont., a. corporation of, Montana.

' Application June 5,

6 Claims.

This invention relates to improvements in apparatus for feeding water tosteam boilers.

The invention relates particularly to that type 'of apparatuswherein'the water to be fed to the 5 boiler enters a sump or floatchamber under a low or atmospheric pressure, and flows by gravity intothe boiler when the chamber is placed under boiler pressure. The watermay be the condensate from the devices supplied with steam from theboiler or may be fresh water supplied to maintain the proper level inthe boiler.

It is an object of the invention to provide an improved form of controlmeans for governing the admission of steam pressure to the chambe andthe Venting of pressure therefrom.

Another object of the invention is to provide an apparatus including afloat chamber and valves outside the chamber for determining thepressure therein, the float extending to the ex terior of the chamberthrough a flexible, hermetically sealed joint.

A further object is to provide a boiler feed chamber or return traphaving electrically actuated valves which may be, and preferably are, ofthe type in which the moving parts are located entirely within the valvecasings, thus eliminating the usual packings.

Other objects and advantages of the invention will become apparent asthe description proceeds and upon reference to the accompanyingdrawings, wherein- Fig. 1 is a side elevation of the principal parts ofa preferred embodiment of the invention,

Fig. 2 is a similar view with some of the parts 35 broken away andothers in section,

Fig. 3 is an end view of the float chamber as seen with the door of thevalve housing removed,

Fig. 4 is a diagrammatic view showing the application of the inventionto a boiler,

Fig. 5 is a fragmentary circuit diagram of the electrical switch and thevalve operating circuits,

Fig. 6 is a side elevation illustrating a modifled form of theinvention,

Fig. '7 is a sectional view of the control valve 45 shown in Fig. 5, and

Fig. 8 is a side elevation of another modified form of the invention.

In the drawings, the reference numeral I identifies a sump or floatchamber which is positioned above the boiler level and receivescondensate return or feed water through a pipe 2, check valve 3 and pipe4, when the chamber is under low pressure, and discharges water to theboiler 5 through the pipe 2, check valve 6 and feed pipe I when thechamber is under boiler pressure.

1936, Serial No. 83;l79

The chamber I may be provided with an insulating jacket 8, a sight gauge9, a manual drain valve I and,-preferably, with a ring bolt II tofacilitate handling of the chamber during assembly or removal. I AT-fitting I2 opens into the upper part of the float chamber through aperforated pipe I3, and a vent pipe I4 and steam pipe I from the boilerare connected to the fitting I2 through electrically operated valves I6,I'I, respectively. A manual shut-off valve I8 and steam strainer I9 arepreferably included in the steam line I5. The circuits for actuating thevalves are controlled by a float andlever 2I which has a pivotal support22 in a switch housing 23 that is mounted on the endcap 24 of thechamber I, the switch housing being hermetically sealed from the chamberwithout using the customary packed joints by extending the lever 2Ithrough the flexible metal bellows 25.

The outer end of the float lever 2| extends into a notch in thepivotally mounted plate 26 which carries a single mercury switch 2'!having pairs of contacts I6a, I'Ia at its opposite ends or,alternatively,'twooppositely arranged mercury switches each having asingle pair of contacts. One contact of each pair is connected by a lead28 to one side .of thesec'ondary winding of a step-down transformer 29,and the other contacts are connected to the respective solenoids Ifib,I'Ib' of the valves I6, H. The secondary circuit is completed by a lead31! from the other solenoid terminals to the secondary winding. Thetransformer is mounted on a sheet metal casing 3I that provides ahousing for the valves, and the line connections 32 to the primary ofthe transformer are brought in through the usual conduit 33 that issecured to the casing. The closure 3I for the casing is preferably ahinged door which permits ready access to the valves and transformer incase of inspection or repair. e r .The method of operation will beapparent from Fig. 2 and the wiring diagram, Fig. 5. The parts areillustrated in the positions which they occupy when the float hasdropped to its low level operating point, i. e.,the float lever 2I hasrocked the'switch plate 26 counterclockwise to connect contacts 56wthrough the ball of mercury.' The solenoid: I'Eb of the vent valve I6 isenergized, thevalve is lifted and the chamber isopen to the vent pipeI4. Condensate return or feed water flows into the chamber until thefloat 20 is raised to that level which results in ablockwise tilting .ofthe mercury switch by the float lever 2|. The mass of mercury rolls tothe opposite end of the tube, thus opening the contacts 16a to permitvalve Hi to close prior to the closing of the contacts Ila to energizesolenoid Nb of the steam line valve I1. The water trapped in the chamberI can then flow to the boiler by gravity, through pipe 2, check valve 6and feed pipe I. The float drops towards its lower level as the water isfed to the boiler, and the switch plate rocks again to open the circuitof the steam valve solenoid before the circuit of the vent valvesolenoid is closed.

This successive operation of the switches is particularly advantageoussince it eliminates the springs and/or snap-action levers and toggleswhich were used with mechanical control systems to effect anapproximately simultaneous opening of one valve and closing of theother. The electrical control system has the further advantage thatcommercial types of packless valves may be used, thus avoiding thedificulties and annoyance of leaking valves. The electrical control hasthe further advantage that the valves l6, I! close automatically in thecase of electrical.

failure. The system can then be operated manually through bypass lines,for example by connecting a steam line to the drain valve ll! of thefloat chamber or, as shown in Fig. 3, through a by-pass valve [1 whichis controlled by the wheel H.

The successive actuation of the valves may also be effected with asingle solenoid by the arrangements shown in Figs. 6 to 8. The floatchamber of these modified constructions, and the water inlet and outletconnections may be of the described construction, and like parts aretherefore identified by the corresponding reference numerals of Figs. 1to 5.

. As shown in Fig. 6, the perforated steam inlet pipe l3, and the ventand steam lines 34, 35 are connected to the casing 36 of a double valvewhich functions as a three-way valve. The solenoid 36a of the valve hasan armature or plunger 3'! that slides in a tube 38 that has a closedupper end for sealing the interior of the valve casing from atmosphere.The vent valve 39 and steam valve 46 are of similar construction, beingpressed towards closed position in the valve seat bushings 4i, 4] bysprings 42, 42'. The operating levers 43, 43' are pivoted upon the valveseat bushings and have curved ends extending into slots in the ventvalve 39 and steam valve 49, respectively. The other ends of the leversare connected tothe plunger 37 through a link 44, and the parts are sodesigned that both valves are seated 'by their springs when the plunger31 and link 44 are in mid-positions.

The switch '21 is a mercury switch of the single pole, single throw typewhich closes the circuit from the transformer 29 to the solenoid 36awhen the float is in raised position. The solenoid is thus energized andthe plunger 3'! is lifted from the position shown in Fig. 7, and thespring 42 forces the vent valve 39 to closed position before the cam endof lever 43 opens the steam valve 46 against the spring 42 that normallyholds the valve closed. The float drops to open the switch 21 as thewater drains from the float chamber to the boiler, and the plunger 3'!drops when the electric circuit is opened. The lever 43 tilts to permitthe closing of the steam valve 46 before lever 43 has moved intoposition to open the vent valve. The double valve thus operates as athree-way valve to isolate the float chamber momentarily from both thevent line and the boiler at each change of pressure conditions withinthe float chamber.

The modified arrangement shown in Fig. 8 includes a large diaphragmoperated steam valve 45 in the steam pressure line 46 to the perforatedinlet pipe I3 of the float chamber I, the diaphragm valve beingcontrolled by the float through electrically actuated valves which maybe, and preferably are, three-way valves such as shown in Fig. 6. Asmall steam pipe 53a is connected between the steam line 46 and thesteam inlet valve of the valve casing 36, and the vent pipe 34 isconnected to the other valve union. Pipe 41 connects the interior of thevalve casing 36 to the diaphragm chamber 48 of the stem valve 45, andthe branch connection 49 from the pipe 41 to the top of the floatchamber l includes a check valve 50 which prevents steam from enteringthe chamber through the branch connection. The steam valve is normallyheld in closed position by a coiled spring 5|, and is moved to openposition by steam pressure in the diagram chamber.

The electrical circuits to the three-way valve are the same as in theFig. 6 construction, and the float chamber is vented to pipe 34 solongas the solenoid 36 of the valve is not energized. When current issupplied to the solenoid, the plunger is lifted and valve 39 closes justprior to the opening of valve 40, see Fig. 5. Steam enters the valvecasing 36 through the pipe 35a when valve 40 is opened, and passes tothe diaphragm chamber 48 to force the main steam valve 45 to openposition, thus placing the float chamber under boiler pressure. When thefloat chamber is emptied, the solenoid circuit is broken and the plungerdrops to close valve 40 and open valve 39. The diaphragm chamber 48 isvented through the pipe 41, valve 39 and vent pipe 34, and the checkvalve 50 will then open to vent the float chamber l to pipe 34.

While I have illustrated typical embodiments of the invention, it is tobe understood that there is considerable latitude in the design andarrangement of the various parts, and that there are numerousarrangements which fall within the spirit of my invention as set forthin the following claims.

I claim:

1. In an apparatus for feeding water to a steam boiler, a chamber, aconduit for supplying water to said chamber, a conduit for feeding waterfrom said chamber to said boiler, check valves for preventing reverseflow in said conduits, a steam supply conduit leading from said boilerto said chamber, a steam supply valve in said conduit, a vent valve insaid connection, independent electrical operating means for said steamsupply and vent valves, control circuits for said operating meansincluding a float actuated switch operative to open the circuitcontrolling one of said valves and thereafter to close the circuit tothe other of said valves dependent upon the level of liquid in saidchamber.

2. In apparatus for feeding water to a boiler, the combination with afloat chamber having a water outlet connection to the boiler and a waterinlet connection, check valves to prevent reverse flow in saidconnections, a steam pressure pipe from the boiler to the chamber, avent pipe for said chamber, and an independent control valve in each ofsaid pipes, said control valves being biased towards closed position, ofcontrol means for operating said control valves in succession to closeone valve and open the other, and a float in said chamber for actuatingsaid control means; said control means including independentelectrically actuated means for operating each of said 'control valves,circuits for energizing said electrically actuated means, and switchesin said circuits and actuated by the float.

3. A boiler feed system of the type including a float chamber locatedabove boiler level, connections for supplying water to said chamber andfor delivering water from said chamber to a boiler when the chamber isunder atmospheric and boiler pressure respectively, and means includinga steam and a vent valve exterior to said chamber for controlling thepressure within said chamber; said means comprising solenoid means foractuating said valves, one wall of said chamber having an openingtherein, a cap member secured over and closing said opening, a switchhousing carried by said cap member, switch means mounted in said switchhousing for controlling circuit connections to said solenoid means, anda float lever extending through thewall of said chamber and said capmember into said switch housing for actuating said switch means.

4. Apparatus as set forth in claim 3, wherein said solenoid meansincludes a solenoid for each valve, and said switch means comprises amercury switch having a pair of contacts at opposite ends foralternatively completing the circuit connections to the respectivesolenoids.

5. In an apparatus for feeding water to a steam boiler, a chamber, meansfor supplying water thereto, a steam connection from said boiler to saidchamber, a steam control valve in said connection, a diaphragm operatorfor said steam valve, a three way valve having one port connected tosaid diaphragm operator and to said chamber, one port connected to saidboiler and one port connected to a vent, electromagnetic operating meansfor said three way valve adapted when energized to close said vent portand open said steam port to admit pressure to said diaphragm and whendeenergized to open said vent port to relieve the pressure on saiddiaphragm, and a control circuit for said electromagnet including aswitch and a float in said chamber for actuating said switch to completethe circuit to said electromagnet upon filling of said chamber and tobreak said circuit upon emptying of said chamber.

6. In a device for feeding water to a steam boiler, a float chamberabove boiler level, connections for supplying water to said chamber andfor delivering water from said chamber to a boiler when the chamber isunder atmospheric and boiler pressure respectively, a steam pipe and avent pipe connected to the upper portion of said chamber, a solenoidoperated valve in each of said pipes, said float chamber having anopening in one end thereof, an end cap member carried by said chamberand closing said opening, a switch housing carried by said end cap, afloat lever within said chamber having an end portion projecting intosaid switch housing through said cap, a flexible bellows sealing thepassage of said lever through said cap, a pivotal mounting for theprojecting end of said lever in said switch housing, a mercury tiltswitch mounted in said switch housing having a notched plate elementloosely embracing the projecting end of said float lever, and saidswitch having a pair of contacts at each end thereof foralternativelycompleting circuit connections to the respective solenoids of said steamand vent valves.

TIMOTHY J. SULLIVAN.

